Thus suppose the number expressed at full length were 3.1415927. If the table extend to no more than four places of decimals, we should tabulate the number 3.1416 and not 3.1415. The former would be evidently nearer to the true number 3.1415927.

Memoirs Ast. Soc. vol. III, p. 65.

Memoirs Ast. Soc. vol. iv., p. 290.

Recueil des Tables Logarithmiques et Trigonometriques. Par J. C. Schulze. 2 vols. Berlin: 1778.

The wheels, and every other part of the mechanism except the axes, springs, and such parts as are necessarily of steel, are formed of an alloy of copper with a small portion of tin.

The machine was constructed with the intention of tabulating the equation Delta^{7}_{u} = 0, but, by the means above alluded to, it is capable of tabulating such equations as the following: Delta^{7}u = a Delta u, Delta^{7}u = aDelta^{3}u, Delta^{7}u = units figure of Delta u.